Functionalized Multi-Walled Carbon Nanotube-Reinforced Epoxy-Composites: Electrical And Mechanical Characterization

Carbon nanotubes (CNTs) got great attention because of their interesting physical and mechanical properties. Due to these interesting properties observed at the nanoscale have motivated scientific community to utilize CNTs as reinforcement in composite materials. In the present study, different CNTs and epoxy nano-composites with different wt% (1, 2, 3, and 4%) of f-MWCNTs were prepared and their surface morphology and orientation has been investigated in detail. Further, the surface investigation, electrical and mechanical tests were carried out on CNTs-filled and unfilled epoxy at maximum sonication time 30 minute to identify the loading effect on the properties of the materials. Experimental results depicts well dispersion of f-MWCNTs, significant improvement that the resistivity of pure epoxy decreased from 108 .m to average value 103 .m with 1, 2, 3, and 4wt% f-MWCNTs. The 4.5wt% CNTs/epoxy was attributed to poor dispersion of f-MWCNTs in the nanocomposte. The hardness of nanocomposite loading 1, 2, 3, 4wt% of CNTs, increased 20.7%, 23.02%, 25.62%, 29.09% respectively as compared to pure epoxy. We believe that our strategy for obtaining CNT–reinforced epoxy nanocomposites is a very promising technology and will open a new doors in fields of aviation, aerospace, marine and sporting goods

Island Size Selectivity during 2D Ag Island Coarsening on Ag (111)

We report on early stages of submonolayer Ag island coarsening on Ag(111) surface at room temperature ($300$ K) carried out using realistic kinetic Monte Carlo (KMC) simulations. We find that during early stages, coarsening proceeds as a sequence of selected island sizes creating peaks and valleys in the island size distribution. We find that island-size selectivity is due to formation of kinetically stable islands for certain sizes because of adatom detachment/attachment processes and large activation barrier for kink detachment. In addition, we find that the ratio of number of adatom attachment to detachment processes to be independent of parameters of initial configuration and also on the initial shapes of the islands confirming that island-size selectivity is independent of initial conditions.These simulations were carried out using a very large database of processes identified by their local environment and whose activation barriers were calculated using the embedded-atom method

Blood urea nitrogen as an early predictor of severity in acute pancreatitis

Background: Acute pancreatitis presents as acute abdominal pain and is usually associated with raised pancreatic enzyme levels in the blood or urine. Aims and objectives of the study was to evaluate the role of serial BUN measurement as an early prognostic marker of acute pancreatitis.Methods: From each patient detailed history was taken, general and systemic examination were done and relevant investigations were conducted. BUN was repeated after 24 hours and the change in the level of BUN was noted. Imaging in the form of CT after 72 hours of admission were performed in each patient. The severity of acute pancreatitis was gauged by modified CTSI and the same was compared to the change in BUN values over first 24 hours of admission.Results: Mean BUN values at ‘0’ hour in severe acute pancreatitis and non-severe acute pancreatitis were 31.91±6.79 and 15.44±5.95 mg/dl, respectively. The difference between the two groups was statistically significant with p value of <0.001. Similarly, the difference in BUN values at ‘24’ hours between the two groups was statistically significant. BUN value ≥23 mg/dl at ‘0’ hour was found to be the optimal cut off for determining the severity of pancreatitis with sensitivity of 91.3%. BUN ≥25 mg/dl at 24 hours was found to be the optimal cut-off for determining the severity of acute pancreatitis with sensitivity of 95.7%.Conclusions: BUN as a single marker for acute pancreatitis can be useful as it is easy to perform and cheap marker to predict severity without the need for complex calculations.

Tuberculosis: an experience at government chest disease hospital

Background: This retrospective study was carried out to find the incidence, clinical profiles and treatment outcome of pulmonary and extrapulmonary tuberculosis patients attending the only Chest Disease Hospital in Srinagar.Methods: A retrospective analysis of 613 patients having EPTB and PTB was undertaken from the chest disease hospital of Government Medical College Srinagar. Demographic characteristics, clinical features and treatment outcome were obtained from medical case records of all patients visiting the hospital for a period of two years from May 2016-May 2018.Results: The study comprised of 613 patients, out of which 365% were having pulmonary TB while 35% were having extrapulmonary TB. Majority of patients (44.5%) in TB group were in age group 10-30 while majority of patients (42%) in EPTB group were in age group 51-70. Males were seen more commonly affected. Majority (90%) of patients in EPTB group had pleural effusion. Majority of patients (71%) were smear positive by ZN staining in PTB group. Majority (90%) of PTB patients in smear negative group were BAL negative. In PTB group 8% were treatment failure while in EPTB group 2% were treatment failure. MDR was seen in 4.2% of total tuberculosis patient while XDR was seen in 0.32% of total patients. Out of treatment failure in PTB group MDR was seen in 64% followed by monoresistance to INH in 30% and XDR in 6%. In EPTB group MDR was seen in 100% of treatment failure. All patients with XDR died. Among the MDR patients majority are on treatment while 12% died, another 12% defaulter while 12% completed treatment.Conclusions: Among evaluated tuberculosis patients, maximum had PTB. Pleural tuberculosis was the most common presentation of EPTB. The study shows male preponderance in both groups. Treatment response was excellent with failure rate of 8% in PTB and 2% in EPTB. Most common cause of failure was MDR. XDR was seen in two patients and both of them died

Recent developments and perspectives in CdS-based photocatalysts for water splitting

Over the past few years, many approaches have been developed progressively to produce hydrogen (H2) from water under solar light irradiation. This process of fuel production is clean, potentially cost-effective, and environment-friendly. At present, however, current technologies are unable to meet the industrial requirements because of high cost, low photoresponse, and insufficient catalytic performance. Among water splitting photocatalysts, CdS is considered to be an interesting and important material owing to its low cost, prominent catalytic activity, high absorption in the visible spectrum, and the suitable positions of its conduction (CB) and valence (VB) bands. There are, however, some associated problems such as the rapid recombination of photogenerated electron–hole pairs and photocorrosion that have severely hampered its practical usage. The efficient conversion of water to H2 depends on the extent to which the charge carriers, especially the electrons, are first generated and then have sufficient life-time for their effective utilization. This review highlights work over the past several years to improve the photocatalytic efficiency and stability of CdS for H2 production from water

Synthesis of 2-{[5-(aralkyl/aryl)-1,3,4-oxadiazol-2- yl]sulfanyl}-N-(4-methyl-1,3-thiazol-2-yl)acetamides: Novel bi-heterocycles as potential therapeutic agents

Purpose: To evaluate the therapeutic potential of new bi-heterocycles  containing a 1,3-thiazole and 1,3,4-oxadiazole in the skeleton against Alzheimer's disease and diabetes, supported by in-silico study. Methods: The synthesis was initiated by the reaction of 4-methyl- 1,3-thiazol-2-amine (1) with bromoacetyl bromide (2) in aqueous basic medium to obtain an electrophile,2-bromo-N-(4-methyl-1,3- thiazol- 2-yl)acetamide (3). In parallel reactions, a series of carboxylic acids, 4a-r, were converted through a sequence of three steps, into respective 1,3,4-oxadiazole heterocyclic cores, 7a-r, to utilize as nucleophiles. Finally, the designed molecules, 8a-r, were synthesized by coupling 7a-r individually with 3 in an aprotic polar solvent. The structures of these bi-heterocycles were elucidated by infrared (IR), electron ionization-mass spectrometry (EI-MS), proton nuclear magnetic resonance (1H-NMR) and carbon nuclear magnetic resonance (13C-NMR). To evaluate their enzyme inhibitory potential, 8a-r were screened against acetylcholinesterase (AChE), but brine shrimp lethality bioassay.Results: The most active compound against AChE was 8l with half-maximal inhibitory concentration (IC50) of 17.25 ± 0.07 μM. Against BChE, the highest inhibitory effect was shown by 8k (56.23 ± 0.09 μM). Compound 8f (161.26 ± 0.23μM) was recognized as a fairly good inhibitor of urease. In view of its inhibition of α-glucosidase, 8o (57.35 ± 0.17μM) was considered a potential therapeutic agent.Conclusion: The results indicate that some of the synthesized products with low toxicity exhibit notable enzyme inhibitory activity against selected enzymes compared with the reference drug, and therefore, are of potential therapeutic interestKeywords: 4-Methyl-1,3-thiazol-2-amine,1,3,4-Oxadiazole,  Cholinesterases, α-Glucosidase, Urease, Brine shrim

Cardiomyocyte Deletion of \u3ci\u3eBmal1\u3c/i\u3e Exacerbates QT- and RR-Interval Prolongation in \u3ci\u3eScn5a\u3c/i\u3e\u3csup\u3e+/ΔKPQ\u3c/sup\u3e Mice

Circadian rhythms are generated by cell autonomous circadian clocks that perform a ubiquitous cellular time-keeping function and cell type-specific functions important for normal physiology. Studies show inducing the deletion of the core circadian clock transcription factor Bmal1 in adult mouse cardiomyocytes disrupts cardiac circadian clock function, cardiac ion channel expression, slows heart rate, and prolongs the QT-interval at slow heart rates. This study determined how inducing the deletion of Bmal1 in adult cardiomyocytes impacted the in vivo electrophysiological phenotype of a knock-in mouse model for the arrhythmogenic long QT syndrome (Scn5a+/ΔKPQ). Electrocardiographic telemetry showed inducing the deletion of Bmal1 in the cardiomyocytes of mice with or without the ΔKPQ-Scn5a mutation increased the QT-interval at RR-intervals that were ≥130 ms. Inducing the deletion of Bmal1 in the cardiomyocytes of mice with or without the ΔKPQ-Scn5a mutation also increased the day/night rhythm-adjusted mean in the RR-interval, but it did not change the period, phase or amplitude. Compared to mice without the ΔKPQ-Scn5a mutation, mice with the ΔKPQ-Scn5a mutation had reduced heart rate variability (HRV) during the peak of the day/night rhythm in the RR-interval. Inducing the deletion of Bmal1 in cardiomyocytes did not affect HRV in mice without the ΔKPQ-Scn5a mutation, but it did increase HRV in mice with the ΔKPQ-Scn5a mutation. The data demonstrate that deleting Bmal1 in cardiomyocytes exacerbates QT- and RR-interval prolongation in mice with the ΔKPQ-Scn5a mutation

Functional Analysis of Hif1 Histone Chaperone in Saccharomyces cerevisiae

The Hif1 protein in the yeast Saccharomyces cerevisie is an evolutionarily conserved H3/H4-specific chaperone and a subunit of the nuclear Hat1 complex that catalyzes the acetylation of newly synthesized histone H4. Hif1, as well as its human homolog NASP, has been implicated in an array of chromatin-related processes including histone H3/H4 transport, chromatin assembly and DNA repair. In this study, we elucidate the functional aspects of Hif1. Initially we establish the wide distribution of Hif1 homologs with an evolutionarily conserved pattern of four tetratricopeptide repeats (TPR) motifs throughout the major fungal lineages and beyond. Subsequently, through targeted mutational analysis, we demonstrate that the acidic region that interrupts the TPR2 is essential for Hif1 physical interactions with the Hat1/Hat2-complex, Asf1, and with histones H3/H4. Furthermore, we provide evidence for the involvement of Hif1 in regulation of histone metabolism by showing that cells lacking HIF1 are both sensitive to histone H3 over expression, as well as synthetic lethal with a deletion of histone mRNA regulator LSM1. We also show that a basic patch present at the extreme C-terminus of Hif1 is essential for its proper nuclear localization. Finally, we describe a physical interaction with a transcriptional regulatory protein Spt2, possibly linking Hif1 and the Hat1 complex to transcription-associated chromatin reassembly. Taken together, our results provide novel mechanistic insights into Hif1 functions and establish it as an important protein in chromatin-associated processes